The present application claims priority to Japanese Applications Nos. P11-381336 filed Dec. 20, 1999 and P2000-070897 filed Mar. 14, 2000, which applications are incorporated herein by reference to the extent permitted by law.
1. Field of the Invention
The present invention relates to an electronic appliance using a housing-case and inner structural members, wherein at least portions of such housing-case and inner structural members are made of biodegradable material and the present invention further relates to a container made of such biodegradable material.
2. Description of the Related Art
For example, electronic appliances are generally put into use for several to ten-odd years and disposed thereafter as refuses. At present, such refuses, except those of some large-sized electronic appliances, are not collected nor recycled. In Japan, recycling of the used alliance is not legally regulated. Thus the most of the electronic appliances becomes non-combustible refuses after once they are disposed. Even small-sized electronic appliances can be a large amount of refuses if the marketing volume thereof is huge. This raises a serious problem when considering the recent shortage in the number (or the capacity) of waste disposal sites.
Incidentally, when the appliances are disposed, a shredding process is applied as the most popular way of a waste treatment to the wasted appliances. The shredding process, however, cannot provide a fundamental solution for the problem, since such waste treatment method can only reduce the volume of the refuses, and the refuses will remain intact for tens and hundreds of years if submitted to landfill. If the shredded dust should be recycled as resources, every parts are finely crashed, and thus even a valuable material such as gold and copper can be mixed with invaluable materials such as resin, which results in degraded purity of materials to be recycled and a poor efficiency in the recovery.
It is therefore a primary object of the present invention to provide an appliance using a housing-case and inner structural members, wherein at least portions of such housing-case and inner structural members are made of biodegradable material, and further this invention relates to a container made of such biodegradable material, because the biodegradable material is not causative of environmental impact even if disposed without any treatment after use.
According to the present invention, at least portions of a structure of an appliance housed in a housing-case and further a container are made of biodegradable material, wherein the thermally deformable temperature [defined in JIS (Japanese Industrial Standard) K7207] of the biodegradable material is preferably above 50xc2x0 C. The biodegradable material is such a material capable of being degraded through the biologic metabolism.
In this specification, the housing-case means a case for housing an appliance such as an electronic appliance and a member which forms a part of a surface of the appliance, and the structural member means a member to keep the strength of the appliance housed in the housing-case. The container means a case to contain a small part such as a cassette tape, a magnetic disc, etc, and further electronic appliances. The electronic appliance includes such as a remote commander and any electronic appliance including circuit boards, a drive device, etc.
In an appliance according to a first embodiment of the present invention, it is preferable that at least almost all of top surface of a housing-case for an appliance are made of biodegradable material and further the melt-flow-rate [defined in JIS (Japanese Industrial Standard) K7207] of such biodegradable material is preferably within 6 to 12.
In an appliance according to a second embodiment of the present invention, the appliance comprises a housing-case, a main unit of the appliance and an optional structural member, wherein at least portions of the housing-case and the structural member are made of biodegradable material, and the portion of the biodegradable material and the portion of non-biodegradable material of the appliance are assembled to be easily separated from each other upon disposal.
In the appliance according to the second embodiment of the present invention, the thermally deformable temperature [defined in JIS (Japanese Industrial Standard) K7207] of the biodegradable material is preferably above 50xc2x0 C.
In an appliance according to a third embodiment of the present invention, the appliance is, for example, a remote commander comprising a printed circuit board and a housing-case to hold the printed circuit board inside. The remote commander is used to control another electronic appliance placed at a remote location by emitting a control infra-red right. In this case, a light emitting portion of the housing-case is made of light transmissive biodegradable material and the other portion of the housing-case is made of impact resistive biodegradable material. The thermally deformable temperature of these biodegradable material is preferably above 50xc2x0 C.
In an appliance according to a forth embodiment of the present invention, a sheet-like panel having buttons formed on its surface by a press forming process is provided as a part of a housing-case of the appliance, wherein the sheet-like panel is made of the biodegradable material.
In the appliance according to the fourth embodiment of the present invention, the thermally deformable temperature of the biodegradable material for the sheet-like panel is preferably above 50xc2x0 C., and a conductive film including binder made of the biodegradable material and conductive material is preferably formed on a back surface of each button. The binder is also made of the biodegradable material of polyester system and a melting point of the biodegradable material for the binder is preferably lower than that of the biodegradable material for the panel.
In an electronic appliance according to a fifth embodiment of the present invention, the appliance has a housing-case comprising a sheet-like panel and a case and both the panel and the case are made of biodegradable material and fixed to each other by adhesive made of biodegradable material. Preferably each of above described biodegradable material has the thermally deformable temperature of higher than 50xc2x0 C.
In an appliance according to a sixth embodiment of the present invention, the appliance comprises a housing-case, a main unit of the appliance and an optional structural member, wherein at least portions of the housing-case and the structural members are made of biodegradable material containing polylactic acid as a major component.
The biodegradable material containing polylactic acid as a major component is a mixture of polylactic acid and the other components, wherein a weight for the other components preferably does not exceed 50% of the total weight. The above mentioned other components preferably comprise a single or a plurality of materials arbitrarily selected from a group consisting of biodegradable organic compound other than polylactic acid and inorganic compound (magnesium hydroxide, talc, carbon, iron oxide, etc).
The organic compound other than polylactic acid is a single or a plurality of materials arbitrarily selected from a group consisting of polybutylene succinate, polycaprolactone, aliphatic polyester (polyhydlactic acid, for example), cellulose acetate-base biodegradable resin, polyvinyl alcohol and natural organic substances (paper, pulp, natural rubber, glue, lacquer, etc.). Preferably the biodegradable material includes only polylactic acid, and the process for disposal becomes more easy and thereby environmental pollution by the disposal is easily avoided.
In the appliance of the present invention, the main unit of the appliance is fixed in the housing-case by screwing, fitting, or adhesion using adhesive so as to allow easy separation of the housing-case from the main unit of the appliance, so that it can readily be separated into the biodegradable members and the non-biodegradable members. In the appliance of the present invention, the push buttons for operating the appliance are provided on the surface of the housing-case, and these push buttons are preferably made of the biodegradable material containing polylactic acid as a major component.
A container according to a seventh embodiment of the present invention, at least a part of the container is made of biodegradable material containing polylactic acid as a major component.
The container of this invention and the appliance of the present invention are preferably constructed as follows.
1) The biodegradable material containing polylactic acid as a major component is a mixture of polylactic acid and other component, wherein a weight of the other component preferably does not exceed 50% of the total weight.
2) The above mentioned other component comprises a single or a plurality of materials arbitrarily selected from a group consisting of biodegradable organic compound other than polylactic acid and inorganic compound (magnesium hydroxide, talc, carbon, iron oxide, etc.).
3) The organic compound other than polylactic acid is a single or a plurality of materials arbitrarily selected from a group consisting of polybutylene succinate, polycaprolactone, aliphatic polyester (polyhydlactic acid, for example), cellulose acetate-base biodegradable resin, polyvinyl alcohol and natural organic substances (paper, pulp, natural rubber, glue, lacquer, etc.).
4) The biodegradable material containing polylactic acid as a major component is composed only of polylactic acid.
5) The main unit of the appliance is fixed to the housing-case by screwing, fitting, or adhesion using an adhesive so as to be easily separated from the housing-case.
6) The container is transparent or semi-transparent in some case.
7) When a movable cover is provided, decomposition or disassembling of the housing-case or the container will become more easy by supporting the movable cover with a pivot bearing in a rotatable manner so as to allow the cover to turn around the pivot bearing and to be fitted to the housing-case or the container to close it.